The present invention relates generally to gas turbine engines, and more particularly to a variable stator vane assembly of a gas turbine engine and to a bushing of such an assembly.
Variable stator vane assemblies have been used in aircraft gas-turbine-engine compressors since 1950. Such compressors contain alternating rows of stator vanes and rotating blades. The vane airfoils of a row of variable stator vanes are turned about their longitudinal axes to a different position for different incoming airflows to straighten the airflow which will encounter the adjacent downstream row of rotating compressor blades. A trunnion is used to turn a vane airfoil, wherein the trunnion is supported by polymeric or graphite bushings installed in a through hole of the compressor casing. The bushings are replaced, as needed, due to wear of the bushings from the trunnion being turned with respect to the bushings.
Still, scientists and engineers continue to seek improved variable stator vane assemblies and improved bushings of variable stator vane assemblies.